Illuminated flush push button switch



March 3l, 1964 B. REED Filed Jan. 25, 1961 ILLUMTNATED FLUSH PUSH BUTTONSWITCH INVENTOR bUcK/ EY R. REED ATTORNEY i United States Patent Oiliee3,127,493 Patented Mar. 31, 1964 3,127,493 HLLUMENATED FLUSH FUSH BUTTONSWITCH Buckley R. Reed, Jailey Station, Ky., assigner to K. M. WhiteCompany, inc., Louisville, Ky., a corporation of Kentucky Filed lau. 23,196i, Ser. No. $4,033 2 (Claims. (Cl. Zim- 167) The present inventionrelates to an illuminated flush push button switch which `is especiallysuitable for use in elevator control systems.

Gne problem encountered with automatic and semiautomatic elevators,which have come into wide-spread use, is the accidental operation ofpush buttons in lobbies and cars due to crowded conditions. Also, thereare a number of important requisites which must be met by a satisfactoryelevator push button switch. For example: it is preferable that theswitch be illuminated, and have good lamp life to minimize maintenance;the switch should operate with a short push button stroke, yet haveadequate Contact gap and long contact life; the switch should be compactso that it easily ts in small and shallow openings. As will be apparent,many of these objectives for a good illuminated push button switch ofthe flush type are to some extent incompatible from the designviewpoint, thus posing difculties in creating a satisfactory switch ofthis hind.

It is a principal object of the present invention to provide a new,improved ilush type push button switch in which the outermost part ofthe operating button is substantially ush with the outer switch panelsurface to prevent accidental operation, but `which attords convenientoperation of the push button through beveling of the portion of theswitch body around the push button to provide as ready access to theoperating button as if it projected beyond the surface of the controlpanel in the usual manner.

lt is another obiect of this invention to provide such a iiush type pushbutton switch in which the operating button can be illuminated, or thebeveled switch portion `surrounding the button can be illuminated toprovide a halo eect, or both. It is a related object to provide such anilluminated elevator switch that is so compact it will easily tit in thecar station or hall button box, yet is so designed that it can utilize astandard size lamp, and has two long life lamp contacts, thus providinggood lamp life. lt is another related object of the present invention toprovide such an illuminated switch which is so designed that the lampcan be easily removed yfrom its housing for replacement when necessary.

it is still another object of the present invention to provide such acompact illuminated ilush type push button switch having electricalspring contact mem ers which are so designed that the moving contactbuttons have a substantially longer travel than the switch operatingpush 'J button, thereby providing an adequate gap betwen the movable andfixed contacts with a short push button operating stroke. it is anotherrelated object of the present invention to provide such a compact switchhaving elongated spring contact members in a conned space, thus reducingthe bending stress on these contact members, while permitting longover-travel, thereby providing long contact life and reducingmaintenance.

it is still another object of the present invention to provide a newimproved compact, illuminated, ilush type push button elevator switchwhich has the foregoing `advantages, yet is of simplified constructionso that it can be economically made and has competitive advantages inthe market for which it is intended.

Still other objects and advantages of the present invention will beapparent from the :following description thereof with reference to ltheaccompanying drawings, wherein:

FiGURE l is a side elevation view of the new improved push button switchof the present invention, with part of the switch base and cap beingbroken away to show the push button and other parts more clearly, andwith a fragmentary illustrative showing of cover and mounting plates fora typical switch installation;

FiGURE 2 is a sectional view taken along line 2-2 in lFIGURE l;

FIGURE 3 is a side elevation view of the push lbutton switch of thisinvention (showing the side opposite that shown in FEGURE l);

FIGURE l is a top plan View of the push button switch shown in FlGURESl-3; and

FIGURE 5 is a bottom plan view of the push button switch shown inFIGURES 1 4.

Referring to the drawings, the new improved flush type push buttonswitch or" the present invention is generally indicated by the numeral10 and is shown in FIG- URE l as it would be mounted in a typicalinstallation with conventional mounting plate l2 and cover or panelplate 1li.

Switch lll comprises a main body 16 that is of substmtially rectangularoutline and has a main base portion from which there extend two likesubstantially rectangular end members i8, and a somewhat shorter andwider centrally disposed block Ztl which is also of generallyrectangular shape. As will be apparent, the adjacent sides of ends ld'and centrally disposed block 20 provide a pair of channels 22 whichextended transversely through the main switch body `16 for accommodationof the spring contact members 23 fwhich will be hereinafter Imore fullydescribed.

One side of the centrally disposed block 20 is provided with atransversely extending circular aperture 24 of such diameter `as toreceive the base `26 of a standard bayonet type lamp 2S. The centrallydisposed block 2t) is also provided with a substantially rectangularaperture extending from the bottom surface of the switch body 'lid andhaving opposite side walls 3l), 31, 32 and 33 (as indicated in FIGURE5). As will be especially apparent from FGURE 5, the portion of thisaperture 29 adjacent side 33 does not extend entirely through thecentrally disposed block Zd; and the portion of block 2li which isupwardly disposed in FIGURE 3 is provided with an extension 36 that hasan inside cylindrical surface so that the base 25 of the lamp 23 restsagainst that surface. The circular aperture 2li is provided with a pairof diametrically opposed grooves 3S and dit for receiving the usualbayonet projections on the base 26 of bulb 2S.

A left hand and right hand spring contact 4Z and 44, respective-ly, eachhaving a coniiguration as Shown in FlGURES 2, 3 and 4, is secured to thebase of the main switch body lo by like terminal screws 26, withconventional nuts 43 and lock washers 45, as shown in the drawings.

Referring especially to FIGURES 1 and 5, the end wall 3l. of aperture 29in the bloc; section Ztl of base 7.6 is provided with a concave recesslo that is concentric with the lamp base aperture 24. Thus, lamp 28 isretained in the switch body lo, with its base 26 in aperture t andabutting surface 3d, and with its other end pressed into the concavedepression i8 due to the spring action ot contacts 42 and against theexternal contact buttons 50 of the lamp 28.

Referring particularly to FlGURES l and 5, the end wall 3l of theaperture 29 and the base lo is also provided with a groove 52 as shownin these iigures. This makes it possible to easily remove the lamp 28 byinserting any pointed object into the groove 52, between lamp andhousing, to force lamp 28 against the action of spring contacts 42 and44 and tip the lamp for removal from the aperture 29. To install a newlamp, its base 26 is simply positioned in aperture 24, with the lampbayonet projections in grooves 38 and 40, and the lamp is then pressedinto position so that the end of the bulb is seated within the concaveportion 48.

Referring especially to FIGURES l and 2, each of like spring contactmembers 23 mounted in the switch body channel 22 is substantiallyJ-shaped, with its shorter leg being secured to the base of the mainswitch body 16 by a terminal screw 54 and nut and lock washers 56 and53, respectively. The free end of the longer leg of each J-shapedcontact 23 is provided with a movable contact button 60; and acooperating xed contact screw 62 is mounted in the base of the mainswitch body 16 by means of nut and lock washers 64 and 66, respectively.

The push button switch 1i) further comprises a cap generally indicatedat 6S, which is mounted on the switch body 16 as hereinafter described,and a push button generally indicated at 70, which is reciprocablymounted within cap 68 for operating spring contacts 23, as hereinafteramplilied.

The cap 68 has a configuration which will be apparent from FIGURES 1-4,including a lower rectangular base portion 72 and an upper smallerrectangular portion 74, which is adapted to be received in the apertureof the switch mounting and cover plates 12 and 14 (as shown in FIGUREl). The corners of the lower rectangular cap section 74 may be recessedas at 76 to accommodate the heads of screws 78 which secure the switchcap 63 to the main switch body 16. The underside of switch cap 68 isalso provided at each end with downwardly projecting lugs 80 which arereceived in corresponding rectangular recesses 82 in the top edges ofend walls 13 of main switch body 16 (as shown in dotted line in FIGURES1, 3 and 4).

The switch cap 68 has a centrally disposed circular aperture 84extending through it to accommodate the upper cylindrical portion 86 or"the contact operating push button 70. As will be apparent especiallyfrom FIGURES 1-3, the push button has, at the lower end of cylindricalportion 86, an enlarged ange 88 which is of circular outline. The bottomof flange 88 is provided with a transversely extending groove 9i) ofrectangular outline, thus forming at the lower end of push button 7i) apair of legs 92, each of which is disposed on opposite sides of centralblock 20 of the main switch body 16.

Each of legs 92 is provided with a triangular projection 94, the pointof which engages an intermediate part of the longer leg of the springcontact member 23 which is disposed in the same channel 22, foroperation of the movable contact 60 towards the iixed contact 62. Thepush button flange portion 88 is provided at opposite sides with anarcuate recess 89 which receives the end of projection 80 on theunderside of switch cap 68.

The upper end of aperture 84 in switch cap 63 is bevelled at 95. It willbe noted that the upper part of push button cylinder 86 projects intothe bevelled region 95, but that its top is below the outer surface ofswitch cap 68. Summary of mode of operation: The switch is installedwith the terminal screws 46, 54 and 56 wired into the control circuitsas desired. To operate the switch, the cylindrical part 86 of pushbutton 70 is depressed, thus causing the movable leg of spring Contact23 to bend downward due to depression by the projection 94 of pushbutton 70. This causes the movable contact 60 to engage the fixedcontact screw 62 to complete the control circuit. When the operatorslinger is removed from the push button section 86, the spring action ofthe contact members 23 returns the push button unit 7i) to its positionas shown in FIGURES 1-3. It will be noted that the bevel 95 permitsready access for depression of push button part 86, although the top ofthe latter is substantially ush with the outermost portion of the switchcap 68 and the mounting cover plate 14. The outward travel of the pushbutton unit 68 to open switch position is limited by abutment of the topof the push button flange section 8S with the underside `of the switchcap section 72. As will be apparent, by using the J-shaped contact 223and operating its movable leg intermediate its ends, it is possible toachieve an adequate gap between contacts 6l) and 62 but still operatethe switch with a short push button stroke, while reducing the bendingstress on the Contact members 23 to prolong their life.

The switch cap 63 may be made of a translucent material such as whitePlexiglas, in which case the lighting of lamp 23 will cause a haloelfect in the bevelled region surrounding push button cylinder 86. Thepush button cylinder 36 may also be made of a translucent plasticmaterial, such as Plexiglas, so that the button itself will light up.Alternatively, either the push button cylinder 86 of the switch cap 63may be made of opaque material so that only the button member 86 or thebevelled portion 95 will light up.

The main switch body 16 is also made of a suitable electricallynon-conductive material, such as plastic. When made of plastic, the mainswitch body 16, the switch housing cap portion 68, and the push button70 may each be injection or compression molded, with a configurationsuch as disclosed in the drawings and described herein. Of course, ifdesired, such switch cornponents need not be molded as integral units,and may be made up of sub-sections secured together in any suitablemanner. All contacts and terminals are, of course, made of suitableelectrically conductive material.

It will be apparent from the foregoing that the present inventionprovides a new improved compact, illuminated, iiush type push buttonswitch which achieves the objects and advantages discussed earlier inthis application and is especially satisfactory for elevatorinstallations.

The invention may be embodied in other specic forms without departingfrom the spirit or essential characteristics thereof. The presentembodiment is therefore to be considered in all respects as illustrativeand not restrictive, the scope of the invention being indicated by theappended claims rather than by the foregoing description, and allchanges which come within the meaning and range of equivalency of theclaims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States LettersPatent is:

1. A switch comprising: a housing of electrically nonconductivematerial, including a base portion with a section of the housingextending laterally therefrom; an electrically conductive iixed contacton the housing base portion on each side of said laterally extendingsection; an electrically conductive movable contact member disposed onthe switch housing base portion on opposite sides of said laterallyextending housing section, each of said contact members comprising apair of legs connected by an intermediate arcuate section, one of saidlegs being secured to said switch housing base portion and the other ofsaid legs being relatively elongated and biased away from but movable toengagement with said fixed contact; said switch housing including a capportion with an aperture therein; push button means reciprocably mountedin said aperture, said push button means including a projection on eachside of said housing section engaging the corresponding biased movablecontact leg intermediate its ends, so that the free end portion of eachof said movable contact legs engageable with its corresponding lixedcontact has a greater travel than said push button means for switchoperation, thereby providing adequate contact gap with small switchoperating movement; an aperture in said housing section which extendslaterally from said switch housing base portion, said `aperture beingadapted to support the base of a lamp; an additional opening in ysaidhousing base portion and said laterally extending housing section tforaccommodating the body of a lamp; at least one `spring contact member onsaid switch housing adjacent said aperture adapted to engage the base ofa lamp in said aperture, means for aligning a lamp in said aperture inelectrical engagement with said spring contact member, and a depressionin the opposing wall of said additional opening in said lamp baseportion, whereby the spring action of said lamp Contact causes a portionof the lamp installed in the housing to be held in said depression; saidswitch further comprising a recess in said opposing wall of saidadditional housing opening extending between the exterior of the housingand said depression, thereby permitting insertion of an object forremoval of a lamp in said housing opening.

2. A switch comprising: a housing of electrically nonconductivematerial, including a lbase portion and a cap portion; at least one setof cooperating electrically conductive contacts on said switch housingbase portion; push button means reciprocably mounted in said switch capportion and adapted to operate said contact means; the exterior of saidhousing cap portion being bevelled around the external end of said pushbutton means, with the outermost portion of said push button means beingdisposed between the inner and outer limits of said bevelled part of theswitch housing cap portion; an aperture in said switch housing adaptedto receive a base of a lamp, with an additional opening in said switchhousing for accommodating the body of a lamp; at least one springcontact member on said switch housing adjacent said lamp base aperture,means for aligning va lamp in said aperture in electrical engagementwith said spring contact member, and a depression in the opposing wallof said additional opening in said lamp base portion, whereby the springaction of said lamp contact causes a portion of the lamp installed inthe housing to ybe held in said depression; at least one of said pushbutton means and said bevelled cap portion of the switch housing beingnon-opaque lfor illumination thereof by a lamp installed in the switchhousing; said switch yfurther comprising a recess in said opposing wallof said additional switch housing opening extending between the exteriorof the housing and said depression, thereby permitting insertion of anobject for removal of a lamp in said housing opening.

References Cited in the le of this patent UNITED STATES PATENTS2,273,353 Harris Feb. 17, 1942 2,689,276 Worel Sept. 14, 1954 2,802,082Kalwo Aug. 6, 1957 2,958,752 Herman Nov, 1, 1960

2. A SWITCH COMPRISING: A HOUSING OF ELECTRICALLY NONCONDUCTIVEMATERIAL, INCLUDING A BASE PORTION AND A CAP PORTION; AT LEAST ONE SETOF COOPERATING ELECTRICALLY CONDUCTIVE CONTACTS ON SAID SWITCH HOUSINGBASE PORTION; PUSH BUTTON MEANS RECIPROCABLY MOUNTED IN SAID SWITCH CAPPORTION AND ADAPTED TO OPERATE SAID CONTACT MEANS; THE EXTERIOR OF SAIDHOUSING CAP PORTION BEING BEVELLED AROUND THE EXTERNAL END OF SAID PUSHBUTTON MEANS, WITH THE OUTERMOST PORTION OF SAID PUSH BUTTON MEANS BEINGDISPOSED BETWEEN THE INNER AND OUTER LIMITS OF SAID BEVELLED PART OF THESWITCH HOUSING CAP PORTION; AN APERTURE IN SAID SWITCH HOUSING ADAPTEDTO RECEIVE A BASE OF A LAMP, WITH AN ADDITIONAL OPENING IN SAID SWITCHHOUSING FOR ACCOMMODATING THE BODY OF A LAMP; AT LEAST ONE SPRINGCONTACT MEMBER ON SAID SWITCH HOUSING ADJACENT SAID LAMP BASE APERTURE,MEANS FOR ALIGNING A LAMP IN SAID APERTURE IN ELECTRICAL ENGAGEMENT WITHSAID SPRING CONTACT MEMBER, AND A DEPRESSION IN THE OPPOSING WALL OFSAID ADDITIONAL OPENING IN SAID LAMP BASE PORTION, WHEREBY THE SPRINGACTION OF SAID LAMP CONTACT CAUSES A PORTION OF THE LAMP INSTALLED INTHE HOUSING TO BE HELD IN SAID DEPRESSION; AT LEAST ONE OF SAID PUSHBUTTON MEANS AND SAID BEVELLED CAP PORTION OF THE SWITCH HOUSING BEINGNON-OPAQUE FOR ILLUMINATION THEREOF BY A LAMP INSTALLED IN THE SWITCHHOUSING; SAID SWITCH FURTHER COMPRISING A RECESS IN SAID OPPOSING WALLOF SAID ADDITIONAL SWITCH HOUSING OPENING EXTENDING BETWEEN THE EXTERIOROF THE HOUSING AND SAID DEPRESSION, THEREBY PERMITTING INSERTION OF ANOBJECT FOR REMOVAL OF A LAMP IN SAID HOUSING OPENING.